Cable lead-through device

ABSTRACT

The invention relates to a device for covering and sealing a hole ( 10 ) through a wall provided for leading cables therethrough, said hole being provided in, for example, a switchgear cabinet. The device comprises a retaining frame ( 16 ), which can be fastened to the edge ( 66 ) of the hole through the wall ( 12 ), and comprises a number of bushes ( 30, 31 ), which are made of elastomeric material, can be removeably inserted inside frame openings ( 28 ), and which can be fixed therein. A least one part of the bushes ( 30, 31 ) is provided with at least one through opening for a cable. In order to equip the cable leadthrough with cables in a particularly easy manner and to be able to mount it on the switchgear cabinet, the invention provides that the frame openings ( 28 ) are open on one side for inserting the bushes ( 30, 31 ). In addition, one of the bushes ( 31 ), which can be inserted into the frame openings, can be arrested in a direction of insertion in the area of the sidewalls ( 36 ) that delimit the frame openings ( 34 ).

CROSS REFERENCE TO RELATED APPLICATIONS

Applicant claims priority under 35 U.S.C. §119 of German Application No.103 13 989.3 filed on Mar. 27, 2003. Applicant also claims priorityunder 35 U.S.C. §365 of PCT/EP2004/000479 filed on Jan. 22, 2004. Theinternational application under PCT article 21(2) was not published inEnglish.

The invention relates to a device for covering and sealing a holethrough a wall, intended for leading cables through the latter, forexample in a switchgear cabinet. Known devices of this type have aretaining frame which can be fastened to the edge of the hole throughthe wall, and several bushes made of elastomer material, which can beremovably inserted into frame openings and fixed in place there. Atleast one part of the bushes is provided with at least one passageopening for a cable, which is accessible from the outside by way of anedge gap.

The frame openings are open on one side for insertion of the bushes, andat least one of the bushes that can be inserted into the frame openings,in each instance, can be fixed in place in the insertion direction, inthe region of the side walls that delimit the frame opening.

Devices of this type serve to introduce cables provided with plug-indevices or the like into a switchgear cabinet, without having to releasethe plug-in device from the cables. The devices furthermore have thetask of covering and sealing the hole through the wall after the cableshave been introduced. The hole through the wall is generally configuredto be rectangular, and is so large that the cables with the plug-indevices can be introduced.

Cable lead-throughs are known (DE-A-44 34 202, WO99/06747), the framesof which consist of several frame parts made of rigid plastic material,which complement one another to form a complete frame. The frame partshave openings that face one another in pairs and have an open edge,which openings complement one another to form closed frame openings foraccommodating the elastomer bushes, in the connected state of the frameparts. The bushes, in turn, are provided with passage openings for thecables, which are accessible from the outside by way of edge slits thatcan be widened elastically. The frame parts equipped with the bushes setonto the cables in the loose state are connected with one another bymeans of screw connections, while the bushes are pressed together.Subsequently, the frames pre-finished in this manner are fastened to theswitchgear cabinet in the region of the hole in the wall, in such amanner that the one cable ends point into the interior of the switchgearcabinet. In the case of the known cable lead-throughs, it is felt to bea disadvantage that the handling of the divided frames duringpre-assembly is relatively complicated.

A device of the type stated initially is known from GB 2 337 870 A. Ithas a frame that can be attached to the edge of the hole through thewall. The frame has an opening into which several cable bushes can beinserted, some of which are provided with one or more passage openingsfor a cable. On one side, the retaining frame has a flap by way of whichthe frame opening can be opened on one side for insertion of the bushes.By closing the flap, the bushes inserted into the frame opening arefixed in place. In this device, as well, the retaining frame istherefore structured in two parts, so that handling is relativelycomplicated.

Proceeding from this, the invention is based on the task of developing acable lead-through device for switchgear cabinets that can be equippedwith cables and mounted on the switchgear cabinet in particularly simplemanner.

To accomplish this task, the combination of characteristics indicated inclaim 1 is proposed. Advantageous embodiments and further developmentsof the invention are evident from the dependent claims.

The solution according to the invention essentially consists in the factthat instead of the divided frame elements, a one-piece retaining frameis used, the frame openings of which are preferably open on one side forinsertion of the bushes, preferably crosswise to the passage opening,whereby at least one of the bushes that can be inserted into the frameopenings, in each instance, can be arrested, preferably arrested in theinsertion direction, in the region of the side walls that delimit theframe openings, preferably arrested in place. For that, the side wallsof the frame openings are provided with catch depressions foraccommodating catch organs that project laterally, partially above thesurface of the bush. In addition the bushes can be provided with lateralcatch depressions for accommodating catch organs that project towardsthe inside, partially above the side walls.

An advantageous embodiment of the invention provides that the catchorgans are embedded at least partially into the elastomer bush material.It is advantageous if the catch organs are configured with bendingelasticity. They can consist of a rigid or rigid elastic component, forexample of plastic or metal, that is embedded into the elastomer bushmaterial. It is practical if a cavity is located within the bushmaterial, into which the catch organ dips temporarily during theengagement process. Another preferred embodiment of the inventionprovides that at least one part of the bushes consists of two bushhalves that face one another on the side of the passage opening, andmutually complement one another, which have one of the catch organs orone of the catch depressions on sides facing away from one another, ineach instance. In this connection, it is practical if the two bushhalves are configured and disposed as mirror images of one another.Preferably, the bush halves are connected with one another, at one join,preferably in one piece, in hinge-like manner, and open on the side thatlies opposite the join. The open side can be bent open about thehinge-like connection, so that a cable can be introduced onto thepassage opening radially from the outside. It is advantageous if thebush halves are connected in one piece with one another by way of a filmhinge. The catch organs can be embedded in one of the bush halves, ineach instance, as separate components. Alternatively to this, the catchorgans can be connected with one another by way of a stay thatpenetrates or surrounds the bush.

It is practical if the catch organs have a spring stay that is orientedparallel to the side wall of the bush in question and can be bent into acavity in the bush material, and a catch cam that is molded onto thefree end of the spring stay, whereby the catch cam can have a run-upincline that faces in the insertion direction and a catch surface thatfollows the run-up incline, at the back, facing opposite the insertiondirection. It is practical if the catch depressions in the side wallsare formed to be complementary to the catch cams.

It is practical if the side walls of the frame openings that lieopposite one another are oriented parallel to one another, whereby thecatch depressions or catch projections on the side walls of each frameopening lie opposite one another in a mirror image.

According to another preferred embodiment of the invention, the passageopenings of the bushes are disposed outside the center in the insertiondirection, forming two wall parts of unequal thickness. In thisconnection, it is practical if the catch organs are disposedasymmetrically on the side of the thicker wall part, in the region ofthe side walls.

Another preferred embodiment of the invention provides that two bushesof a frame opening, in each instance, are disposed in such a manner thatthey rest against one another with their thinner, preferably slit wallparts, and face away from one another with their thicker wall parts,which are connected with one another in hinge-like manner. In thisconnection, only one of the two bushes can be arrested in place, in eachinstance, forming the closure piece with the side walls of the frameopening.

The retaining frame can be fixed in place at the edge of the holethrough the wall, preferably screwed on. Another preferred embodiment ofthe invention provides that the essentially rectangular retaining framehas two closed narrow side edges and only one closed broad side edge. Tofix the retaining frame in place on the wall, the retaining frame can beprovided with fixation tabs that project towards the side of the holethrough the wall and can be arrested at the edge of the hole through thewall, in the region of its closed narrow side edges, whereby thefixation tabs can be configured as loose components that are fixed inplace with a positive lock in structurally adapted insertion openings inthe closed narrow side edges of the retaining frame. An advantageousembodiment of the invention provides that the fixation tabs have a catchpocket that engages into the edge of the hole through the wall, as wellas a catch organ that can engage on the retaining frame in the region ofthe insertion opening, as well as an activation organ that projectsbeyond the retaining frame on the front, to produce or release the catchconnection with the edge of the hole through the wall.

In the following, the invention will be explained in greater detailusing the exemplary embodiments shown schematically in the drawing.These show:

FIG. 1 a cable lead-through device completely equipped with bushes,mounted in a wall detail;

FIG. 2 a the cable lead-through device according to FIG. 1, which isonly partially equipped with bushes, for illustrative purposes;

FIGS. 2 b, c, and d, a top view and two side views of the cablelead-through device according to FIG. 2 a, equipped with only twobushes;

FIG. 3 a an illustrative representation of a two-part cable bush forinsertion into the cable lead-through device according to FIGS. 1 and 2;

FIGS. 3 b, c, and d, three side views of the two-part bush according toFIG. 3 a;

FIG. 4 a an illustrative representation of a cable bush modified ascompared with FIG. 3 a, for insertion into the cable lead-through deviceaccording to FIGS. 1 and 2;

FIG. 4 b to e, four side views of the cable bush according to FIG. 4 a;

FIG. 5 a an illustrative representation of a fixation tab for fasteningthe cable lead-through device in the region of the hole through thewall;

FIG. 5 b to d, three side views of the fixation tab according to FIG. 5a.

The components shown in the figures, all together, form a cablelead-through device that is intended for insertion into a hole 10through a wall, in an outer wall 12 of a switchgear cabinet. The deviceserves to introduce cables provided with plug-in devices or the likethrough the hole 10 through the wall, into the switchgear cabinet,without having to release the plug-in devices from the cables. The hole10 through the wall is configured to be rectangular and is so large thatthe cables can be introduced with the plug-in devices.

The cable lead-through device 14 has an essentially rectangularretaining frame 16, which is closed on the two narrow side edges 18 andthe broad side edge 20, and open on the opposite side 22. The retainingframe 16 has several ribs 24 that are oriented parallel to the narrowside edges 18, which ribs delimit a corresponding number of frameopenings 26 for accommodating bushes 30, 31 made of elastomer material.The frame openings 28 are open towards the side 22 of the retainingframe 16, so that the bushes 30, 31 can be pushed into the frameopenings 28 from the open side 22. The parallel guidance of the bushes30, 31 in the region of the frame openings 28 takes place in a mannersimilar to the case of DE-C 36 19 183, by means of edge beads 69 on theoutside of the bushes 30, which engage in the side walls 36 at the edge.

The bushes 30, 31 have a passage opening 32 for a cable, not shown,which is accessible radially from the outside, in each instance. Inorder to be able to introduce the cables into the passage openings 28,the bushes 30, 31 are either provided with edge openings 34 that can bewidened elastically (FIG. 4 a to e) or they are configured in two parts(FIG. 3 a to d).

A peculiarity of the cable lead-through devices shown consists in thefact that the bush 31 disposed close to the opening, in each instance,can be arrested in the insertion direction, in the region of the sidewalls 36 that delimit the frame openings 28. For this purpose, the sidewalls 36 of the frame openings 28 are provided with catch depressions 38for accommodating catch organs 42 that project laterally partiallybeyond the bush surface 40. The catch organs 42 have a leaf-spring-likespring stay 44 oriented parallel to the bush wall 40 in question, and acatch cam 46 molded on at the free end of the spring stay. The catch cam46 is provided with a run-up incline 48 that faces in the insertiondirection, and a catch surface 50 that follows the run-up incline at theback, opposite the insertion direction. Within the bush material, acavity 52 is formed and assigned to the catch organ 42, in eachinstance, into which the catch organ 42 temporarily dips during theengagement process. The catch depressions 38 in the side walls 36 areformed to be complementary to the catch cams 46.

In the case of the exemplary embodiment configured in FIG. 3 a to d, thebushes 30, 31 consist of two bush halves 31′, 31″, facing one another onthe side of the passage opening 32, configured as mirror images andmutually complementing one another, in which an independent catch organ42 is embedded, in each instance. The bush halves 31′, 31″ can beconnected in one piece with one another, at their joins 54, for examplewith a film hinge 55 that extends over the entire width in FIG. 3 b,indicated symbolically, while they are open at their opposite joins 56,forming an insertion gap for the cables.

In the case of the exemplary embodiment shown in FIG. 4 a to e, aone-piece bush 30, 31 of elastomer material is provided, which has anedge opening 34 that can be widened elastically, for introducing a cableinto the passage opening 32, and whose catch organs 42 are connectedwith one another by way of a connecting stay 60 at the root 58 of theirspring stays 44. In this connection, the connecting stay 60 can beembedded in the elastomer bush material. The catch cams 46 also have arun-up incline 48 and a catch surface 50, with which they can engage inthe catch depressions 38 in the side walls 36 of the frame openings 28,which are configured to be complementary.

As is particularly evident from FIGS. 2 b, 3 b, and 4 b, the passageopenings 32 are disposed asymmetrically in the cable bushes, in theinsertion direction. As a result, the bush wall 62 on the side of theedge opening 64 is configured to be thinner-walled than the bush wall 64on the opposite side. There is sufficient space for the catch organs 42in the thick-walled bush wall 64.

The thick-walled bush walls 34 overlap the edge 66 of the hole 10through the wall 12 and are pressed against this edge during assembly,forming a seal (see FIG. 2 b).

Fixation of the retaining frame 16 on the wall 12 can take place eitherby means of screws, which pass through four bores 68 towards the wall10, disposed at the frame corners.

Alternatively to this, the exemplary embodiment shown in FIGS. 1, 2, and5 has a simple plug-in connection for fixation of the retaining frameequipped with the bushes, in the region of the hole through the wall.For this purpose, the retaining frame 16 contains a slit-shapedpass-through opening 70 for a fixation tab 72, in each instance, in theregion of its two narrow side walls 18. The fixation tab has a catchpocket 74 on its side facing the hole 10 through the wall, whichsurrounds the edge 66 of the hole through the wall 10, as well as anactivation organ 76 that passes through the pass-through opening 70towards the front. On the front, the fixation tab is additionallysecured on the retaining frame 16 with a catch element 78 that projectsbeyond the edge of the pass-through opening 70.

In summary, the following should be stated: The invention relates to adevice for covering and sealing a hole 10 through a wall intended forleading cables through the latter, for example in a switchgear cabinet.The device has a retaining frame 16 that can be fastened to the edge 66of the hole through the wall 12, and several bushes 30, 31 made ofelastomer material, which can be removably inserted inside frameopenings 28, and fixed in place there. At least one part of the bushes30, 31 is provided with at least one passage opening for a cable. Inorder to be able to equip the cable pass-through with cables and mountit on the switchgear cabinet in particularly simple manner, it isproposed, according to the invention, that the frame openings 28 areopen on one side for insertion of the bushes 30, 31, and that one of thebushes 31 that can be inserted into the frame openings, in eachinstance, can be arrested in place in the insertion direction, in theregion of the side walls that delimit the frame openings 34.

1. A device for covering and sealing a hole provided for leading cablesthrough a wall comprising: (a) a retaining frame fastenable to an edgeof the hole; (b) a plurality of bushes made of an elastomeric material,each bush having a bush surface and at least one part comprising atleast one passage opening for a cable; and (c) a plurality of frameopenings, each frame opening being open on one side for insertion in aninsertion direction of a respective one of the bushes; wherein at leastone of the bushes insertable in the respective frame opening is fixablein place in the insertion direction near side walls delimiting the frameopening; wherein each side wall comprises a catch depression foraccommodating catch organs projecting laterally partially above the bushsurface.
 2. The device according to claim 1, wherein each frame openingis open crosswise to the at least one passage opening.
 3. The deviceaccording to claim 1, wherein the at least one bush can be arrested inthe insertion direction.
 4. The device according to claim 1, wherein thebushes are provided with lateral catch depressions or catch edges foraccommodating catch organs on the side walls that project inward,partially above the side walls.
 5. The device according to claim 1,wherein the catch organs are embedded at least partially in the bushmaterial.
 6. The device according to claim 1, wherein the catch organsare configured to be bendably elastic.
 7. The device according to claim1, wherein the catch organs comprise a rigid or rigid elastic componentembedded in the bush material made of plastic or metal.
 8. The deviceaccording to claim 1, wherein a cavity assigned to the catch organ isdisposed within the elastomeric material, the catch organ dippingtemporarily into said cavity during engagement.
 9. The device accordingto claim 1, wherein at least one part of the bushes comprises two bushhalves that face one another on the side of the passage opening, andmutually complement one another with mirror symmetry, which have a catchorgan on sides facing away from one another, in each instance.
 10. Thedevice according to claim 9, wherein the bush halves are connected withone another, at one juncture in one piece, in hinge-like manner, and areopen on the side that lies opposite the juncture, forming an edgeopening.
 11. The device according to claim 10, wherein the bush halveshave a film hinge at the juncture.
 12. The device according to claim 1,wherein the side walls that delimit the frame openings and lie oppositeone another are oriented parallel to one another.
 13. The deviceaccording to claim 12, further comprising catch depressions or catchprojections assigned to the frame openings and disposed opposite oneanother as mirror images on the related side walls.
 14. The deviceaccording to claim 1, wherein the passage openings of the bushes aredisposed outside the center in the insertion direction, forming firstand second wall parts of unequal thickness, said first wall part beingthinner than said second wall part.
 15. The device according to claim14, wherein the catch organs of the bushes are asymmetrically disposedon the side of the second wall part.
 16. The device according to claim14, wherein two bushes are disposed in a respective frame opening, insuch a manner that the first wall part of each of said two bushes restagainst one another and the second wall part of each of said two bushesface away from one another.
 17. The device according to claim 16,wherein only one bush can be arrested in each frame opening, in eachinstance, with the side walls of the frame opening.
 18. The deviceaccording to claim 1, wherein the retaining frame can be screwed ontothe edge of the hole through the wall.
 19. The device according to claim1, wherein the retaining frame is substantially rectangular and hasfirst and second closed narrow side edges, a closed first broad sideedge, and an open second broad side edge opposite to said open firstbroad side edge.
 20. The device according to claim 19, wherein theretaining frame is provided with fixation tabs that project towards theside of the hole through the wall, and can be arrested on the edge ofthe hole through the wall, in the region of its closed narrow sideedges.
 21. The device according to claim 20, wherein the fixation tabsare configured as loose components that can be fixed in place with apositive lock in an adapted pass-through opening in the closed narrowside edges of the retaining frame.
 22. The device according to claim 20,wherein the fixation tabs have a catch pocket that surrounds the edge ofthe hole through the wall, as well as a catch element that can engage onthe retaining frame in the region of the pass-through opening.
 23. Thedevice according to claim 20, wherein the fixation tabs have anactivation organ that projects beyond the retaining frame on the front,to produce and/or release the catch connection with the edge of the holethrough the wall.
 24. The device according to claim 1, wherein eachcatch organ has a spring stay with a free end and a catch cam moldedonto the free end of the spring stay, said spring stay being orientedparallel to the side wall of the bush or the bush halves and bendableinto a cavity in the elastomeric material in spring-like manner.
 25. Thedevice according to claim 1, wherein the catch organs are embedded inone of the bush halves, in each instance, as components that areseparate from one another.
 26. The device according to claim 1, whereinthe catch organs are connected with one another by way of a connectingstay that penetrates or surrounds the bush.
 27. The device according toclaim 24, wherein the catch cams have a run-up incline that faces in theinsertion direction, and a catch surface that follows the run-up inclineat the back, facing opposite the insertion direction.
 28. The deviceaccording to claim 24, wherein the catch depressions in the side wallsare formed to be complementary to the catch cams of the bushes that forma closure piece.
 29. A bush for a cable lead-through device having aretaining frame provided with frame openings having side walls, saidbush comprising an elastomeric material, at least one passage openingfor a cable, and two catch organs that project beyond the bush surfacetowards opposite sides, which can engage into catch depressions in theside walls of the frame openings; wherein said bush comprises two bushhalves that face one another on the side of the passage opening, andmutually complement one another, which have a catch organ on sidesfacing away from one another, in each instance.
 30. The bush accordingto claim 29, wherein the catch organs are at least partially embedded inthe elastomeric material.
 31. The bush according to claim 29, whereinthe catch organs are configured to be bendably elastic.
 32. The bushaccording to claim 29, wherein the catch organs comprise a rigid orrigid elastic component embedded in the bush material made of plastic ormetal.
 33. The bush according to claim 29, wherein a cavity is formedwithin the elastomeric material, into which a catch organ can be bentduring engagement.
 34. The bush according to claim 29, wherein the bushhalves are connected with one another, at a first juncture in one piece,in hinge-like manner, and are open on an opposite second juncture,forming an edge opening that leads to the passage opening.
 35. The bushaccording to claim 34, wherein the bush halves have a film hinge at thefirst juncture.
 36. The bush according to claim 29, wherein each catchorgan has a spring stay with a free end and a catch cam molded onto thefree end of the spring stay, said spring stay being oriented parallel totwo opposite side walls and bendable into a cavity in the elastomericmaterial.
 37. The bush according to claim 29, wherein the catch organsare embedded in the elastomeric material as components that are separatefrom one another.
 38. The bush according to claim 29, wherein the catchorgans are connected with one another by way of a connecting stay thatpenetrates or surrounds the bush.
 39. The bush according to claim 29,wherein each catch organ has a catch cam comprising a run-up incline anda catch surface that follows the run-up incline by way of a catch edge.40. The bush according to claim 29 wherein said two bush halves mutuallycomplement one another with mirror symmetry.
 41. A bush for a cablelead-through device having a retaining frame provided with frameopenings having side walls, said bush comprising an elastomericmaterial, at least one passage opening for a cable disposed outside acentral portion forming two wall parts of unequal thickness, and twocatch organs that project beyond the bush surface towards oppositesides, which can engage into catch depressions in the side walls of theframe openings.
 42. The bush according to claim 41, wherein the catchorgans are disposed on the side of the thicker wall part.